The present invention relates to a method for improving the in vivo strength retention of a bioabsorbable implantable medical device, e.g., a suture, staple, clip, pin, screw, ring, implant, prosthesis, etc., and to the resulting medical device. More particularly, the invention is directed to improving the in vivo strength retention of such a device by incorporating at least one basic metal compound into the bioabsorbable polymer from which the device is fabricated.
U.S. Pat No. 4,496,446 discloses a method of reducing the initial in vivo strength retention of surgical devices manufactured from polymers having a glycolic ester linkage by incorporating fillers such as barium sulfate, magnesium oxide, etc., into the polymers. The lowest disclosed level of use of filler was 12.5% in the case of barium sulfate-filled polyglycolic acid rods.